scholarly journals Rain drop size distribution characteristics of cyclonic and north east monsoon thunderstorm precipitating clouds observed over Kadapa (14.47°N, 78.82°E), Tropical semi-arid region of India

MAUSAM ◽  
2022 ◽  
Vol 64 (1) ◽  
pp. 35-48
Author(s):  
S.BALAJI KUMAR ◽  
K.KRISHNA REDDY
Keyword(s):  
Convective Cloud ◽  
Convective Precipitation ◽  
Monsoon Precipitation ◽  
Average Mass ◽  
North East ◽  
Stratiform Region ◽  
Stratiform Clouds ◽  
Rain Drop ◽  
Semi Arid Region ◽  
Precipitating Clouds

Hkkjr ds vkU/kz izns’k jkT; ds v/kZ'kq"d HkwHkkx] dM+ik ¼14-47 fMxzh m-] 78-82 fMxzh iw- ½ esa yxk, x, d.k ds vkdkj vkSj osx ¼ikjohosy½ okys fMLMªksehVj l ‘ty’ pØokr ls mRiUu o"kZ.k es?kksa ¼07 uoEcj 2010½ rFkk mRrj iwoZ ¼,u- bZ-½ ekulwu xtZ okys rwQku ds o"kZ.k es?kksa ¼16 uoEcj 2010½ ds cw¡n ds vkdkj ds forj.kksa ¼vkj- ,l- Mh-½ dks ekik x;k gSA izs{k.kkRed ifj.kkeksa ls gesa ;g irk pyk gS fd pØokr dh otg ls mRiUu o"kZ.k es?kksa esa laoguh o"kZ.k izcy jgkA tcfd mRrj iwoZ ekulwu ds ekeys esa xtZ okys rwQku o"kZ.k laoguh es?k ds Hkkx Lrjh es?kksa dh rwyuk esa vf/kd gSaA pØokr ls mRiUu o"kZ.k] mRrj iwoZ  ekulwu o"kZ.k dh rqyuk esa Lrjh {ks= ¼laoguh {ks=½ esa NksVh cw¡nksa ¼NksVh vkSj e/;e vkdkj dh cw¡nksa½ ls laca/k gSA Lrjh vkSj laoguh es?k {ks=ksa esa mRrj iwoZ ekulwu o"kZ.k dh rwyuk esa vkSlr nzO;eku Hkkfjr O;kl] pØokr ls mRiUu o"kZ.k dk Dm de gSA o"kkZ dh cw¡nksa ds vkdkj dk izs{k.k pØokrh; vkSj mRrj iwoZ ekulwu xtZ ds lkFk rwQkuksa ds o"kZ.k es?kksa esa vyx rjg dh fHkUurk ns[kh xbZ gSA Raindrop size distributions (RSD) of  “JAL”  Cyclone induced precipitating clouds (7 Nov. 2010)  and North- East (NE) monsoon thunderstorm precipitating clouds (16 November 2010) were measured with a Particle Size and Velocity (PARSIVEL) disdrometer deployed at Kadapa (14.47°N; 78.82°E), a semiarid continental site in Andhra Pradesh state, India. From the observational results we find that stratiform precipitation is predominant than convective precipitation in cyclone induced precipitation clouds.  Where as in the case of NE monsoon thunderstorm precipitation convective cloud fraction is more than stratiform clouds. The cyclone induced precipitation is associated with  higher concentration of small drops (small and middrops) in stratiform region (convective region) than NE monsoon precipitation.  The average mass weighted diameter, Dm of cyclone induced precipitation is less than the NE monsoon precipitation both in stratiform and convective cloud regions.  The observed RSD are found distinctly vary from cyclonic and NE monsoon thunderstorm precipitating clouds.    

scholarly journals Vertical Characteristics of Reflectivity in Intense Convective Clouds using TRMM PR Data

2017 ◽  
Vol 7 (2) ◽  
pp. 58 ◽  
Author(s):  
Shailendra Kumar
Keyword(s):  
Vertical Profile ◽  
Regional Differences ◽  
Vertical Structure ◽  
Convective Cloud ◽  
Convective Precipitation ◽  
Vertical Profiles ◽  
Gangetic Plain ◽  
Convective Clouds ◽  
Trmm Pr ◽  
Precipitation Area

Tropical Rainfall Measuring Mission Precipitation Radar (TRMM-PR) based vertical structure in intense convective precipitation is presented here for Indian and Austral summer monsoon seasons. TRMM 2A23 data is used to identify the convective echoes in PR data. Two types of cloud cells are constructed here, namely intense convective cloud (ICC) and most intense convective cloud (MICC). ICC consists of PR radar beams having Ze>=40 dBZ above 1.5 km in convective precipitation area, whereas MICC, consists of maximum reflectivity at each altitude in convective precipitation area, with at least one radar pixel must be higher than 40 dBZ or more above 1.5 km within the selected areas. We have selected 20 locations across the tropics to see the regional differences in the vertical structure of convective clouds. One of the important findings of the present study is identical behavior in the average vertical profiles in intense convective precipitation in lower troposphere across the different areas. MICCs show the higher regional differences compared to ICCs between 5-12 km altitude. Land dominated areas show higher regional differences and Southeast south America (SESA) has the strongest vertical profile (higher Ze at higher altitude) followed by Indo-Gangetic plain (IGP), Africa, north Latin America whereas weakest vertical profile occurs over Australia. Overall SESA (41%) and IGP (36%) consist higher fraction of deep convective clouds (>10 km), whereas, among the tropical oceanic areas, Western (Eastern) equatorial Indian ocean consists higher fraction of low (high) level of convective clouds. Nearly identical average vertical profiles over the tropical oceanic areas, indicate the similarity in the development of intense convective clouds and useful while considering them in model studies.

scholarly journals Discriminating raining from non-raining clouds at mid-latitudes using meteosat second generation daytime data

2008 ◽  
Vol 8 (9) ◽  
pp. 2341-2349 ◽  
Author(s):  
B. Thies ◽  
T. Nauss ◽  
J. Bendix
Keyword(s):  
Cloud Water ◽  
Convective Precipitation ◽  
Rain Area ◽  
Water Path ◽  
Vertical Extension ◽  
Frontal Systems ◽  
Cloud Water Path ◽  
Precipitating Clouds ◽  
Cloud Top Temperature ◽  
Supply Information

Abstract. A new method for the delineation of precipitation during daytime using multispectral satellite data is proposed. The approach is not only applicable to the detection of mainly convective precipitation by means of the commonly used relation between infrared cloud top temperature and rainfall probability but enables also the detection of stratiform precipitation (e.g. in connection with mid-latitude frontal systems). The presented scheme is based on the conceptual model that precipitating clouds are characterized by a combination of particles large enough to fall, an adequate vertical extension (both represented by the cloud water path; cwp), and the existence of ice particles in the upper part of the cloud. The technique considers the VIS0.6 and the NIR1.6 channel to gain information about the cloud water path. Additionally, the brightness temperature differences ΔT8.7-10.8 and ΔT10.8-12.1 are considered to supply information about the cloud phase. Rain area delineation is realized by using a minimum threshold of the rainfall confidence. To obtain a statistical transfer function between the rainfall confidence and the four parameters VIS

scholarly journals Climatological Behavior of Precipitating Clouds in the Northeast Region of Brazil

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Rayana Santos Araújo Palharini ◽  
Daniel Alejandro Vila
Keyword(s):  
Relative Frequency ◽  
Tropical Rainfall Measuring Mission ◽  
Precipitation Radar ◽  
Convective Clouds ◽  
Strong Signal ◽  
Deep Convective Clouds ◽  
Stratiform Clouds ◽  
Precipitating Clouds ◽  
Data Period

This study aims to analyze the climatological classification of precipitating clouds in the Northeast of Brazil using the radar on board the Tropical Rainfall Measuring Mission (TRMM) satellite. Thus, for this research a time series of 15 years of satellite data (period 1998–2012) was analyzed in order to identify what types of clouds produce precipitation estimated by Precipitation Radar (PR) and how often these clouds occur. From the results of this work it was possible to estimate the average relative frequency of each type of cloud present in weather systems that influence the Northeast of Brazil. In general, the stratiform clouds and shallow convective clouds are the most frequent in this region, but the associated rainfall is not as abundant as precipitation caused by deep convective clouds. It is also seen that a strong signal of shallow convective clouds modulates rainfall over the coastal areas of Northeast of Brazil and adjacent ocean. In this scenario, the main objective of this study is to contribute to a better understanding of the patterns of cloud types associated with precipitation and building a climatological analysis from the classification of clouds.

scholarly journals Aerosol measurements during COPE: composition, size, and sources of CCN and INPs at the interface between marine and terrestrial influences

2016 ◽  
Vol 16 (18) ◽  
pp. 11687-11709 ◽  
Author(s):  
Jonathan W. Taylor ◽  
Thomas W. Choularton ◽  
Alan M. Blyth ◽  
Michael J. Flynn ◽  
Paul I. Williams ◽  
...  
Keyword(s):  
Cloud Condensation Nuclei ◽  
Convective Cloud ◽  
Cloud Formation ◽  
Convective Precipitation ◽  
Cloud Base ◽  
Sea Spray ◽  
Cloud Drop ◽  
Aerosol Mass ◽  
Order Of Magnitude ◽  
The Uk

Abstract. Heavy rainfall from convective clouds can lead to devastating flash flooding, and observations of aerosols and clouds are required to improve cloud parameterisations used in precipitation forecasts. We present measurements of boundary layer aerosol concentration, size, and composition from a series of research flights performed over the southwest peninsula of the UK during the COnvective Precipitation Experiment (COPE) of summer 2013. We place emphasis on periods of southwesterly winds, which locally are most conducive to convective cloud formation, when marine air from the Atlantic reached the peninsula. Accumulation-mode aerosol mass loadings were typically 2–3 µg m−3 (corrected to standard cubic metres at 1013.25 hPa and 273.15 K), the majority of which was sulfuric acid over the sea, or ammonium sulfate inland, as terrestrial ammonia sources neutralised the aerosol. The cloud condensation nuclei (CCN) concentrations in these conditions were  ∼  150–280 cm−3 at 0.1 % and 400–500 cm−3 at 0.9 % supersaturation (SST), which are in good agreement with previous Atlantic measurements, and the cloud drop concentrations at cloud base ranged from 100 to 500 cm−3. The concentration of CCN at 0.1 % SST was well correlated with non-sea-salt sulfate, meaning marine sulfate formation was likely the main source of CCN. Marine organic aerosol (OA) had a similar mass spectrum to previous measurements of sea spray OA and was poorly correlated with CCN. In one case study that was significantly different to the rest, polluted anthropogenic emissions from the southern and central UK advected to the peninsula, with significant enhancements of OA, ammonium nitrate and sulfate, and black carbon. The CCN concentrations here were around 6 times higher than in the clean cases, and the cloud drop number concentrations were 3–4 times higher. Sources of ice-nucleating particles (INPs) were assessed by comparing different parameterisations used to predict INP concentrations, using measured aerosol concentrations as input. The parameterisations based on total aerosol produced INP concentrations that agreed within an order of magnitude with measured first ice concentrations at cloud temperatures as low as −12 °C. Composition-specific parameterisations for mineral dust, fluorescent particles, and sea spray OA were 3–4 orders of magnitude lower than the measured first ice concentrations, meaning a source of INPs was present that was not characterised by our measurements and/or one or more of the composition-specific parameterisations greatly underestimated INPs in this environment.

scholarly journals PERBAIKAN ESTIMASI CURAH HUJAN BERBASIS DATA SATELIT DENGAN MEMPERHITUNGKAN FAKTOR PERTUMBUHAN AWAN

2020 ◽  
Vol 20 (2) ◽  
pp. 67-78
Author(s):  
Adi Mulsandi ◽  
Mamenun Mamenun ◽  
Lutfi Fitriano ◽  
Rahmat Hidayat
Keyword(s):  
Growth Factor ◽  
Satellite Data ◽  
Point Cloud ◽  
Heavy Rainfall ◽  
Convective Cloud ◽  
Cloud System ◽  
Slope Parameter ◽  
Rainfall Estimation ◽  
Coupled Method ◽  
Stratiform Clouds

Intisari Permasalahan utama dalam mengestimasi curah hujan menggunakan data satelit adalah kegagalan membedakan antara awan cumuliform dengan awan stratiform dimana dapat menyebabkan nilai estimasi hujan under/overestimate. Dalam penelitian ini teknik estimasi curah hujan berbasis satelit yang digunakan adalah modifikasi Convective Stratiform Technique (CSTm). CSTm memiliki kelemahan ketika harus menghitung sistem awan konveksi dengan inti konveksi yang sangat luas karena akan memiliki nilai slope parameter kecil, sehingga menghasilkan estimasi curah hujan yang underestimate. Dengan melibatkan perhitungan faktor pertumbuhan awan di algoritma CSTm permasalahan tersebut dapat diatasi. Penelitian ini menerapkan algoritma CSTm dan faktor pertumbuhan awan (CSTm+Growth Factor) untuk mengestimasi kejadian hujan lebat yang menyebabkan banjir di Jakarta pada tanggal 24 Januari 2016 yang digunakan juga sebagai studi kasus di proyek pengembangan model NWP di BMKG. Hasil penelitian menunjukan bahwa perlibatan faktor pertumbuhan awan sangat efektif memperbaiki kelemahan teknik CSTm, diperlihatkan dengan peningkatan nilai korelasi dari 0.6 menjadi 0.8 untuk wilayah Kemayoran dan -0.1 menjadi 0.83 untuk wilayah Cengkareng. Secara umum gabungan teknik CSTm dan faktor pertumbuhan awan dapat memperbaiki estimasi nilai intensitas dan fase hujan. Abstract  The main problem in estimating rainfall using satellite data is a failure to distinguish between cumuliform and stratiform clouds, which can cause under/overestimate of rains. In this research, the Modified Convective Stratiform Technique (CSTm) has been used to estimate rainfall based on satellite data. The weakness of the CSTm technique is defined when calculating the convective cloud system within a widely convective point. Cloud convective will have a low value of parameter slope and produce an underestimate of rainfall. This issue can be resolved by calculating the cloud growth factor on CSTm. CSTm algorithm and cloud growth factor (CSTm+Growth Factor) has been applied to this research to estimate heavy rainfall for floods event in Jakarta area on January 24th, 2016. The result showed that the cloud growth factor is very effective in improving the weakness of rainfall estimation using the CSTm technique. Correlation between estimation and observation rainfall has increased from 0,6 to 0,8 on Kemayoran and from -0,1 to 0,83 on Cengkareng. The coupled method of CSTm and cloud growth factor significantly improve in estimating phase and intensity of rainfall.

scholarly journals Groundwater quality and non-carcinogenic health risk assessment of nitrate in the semi-arid region of Punjab, India

2020 ◽  
Vol 18 (6) ◽  
pp. 1073-1083
Author(s):  
Akshay Kumar Chaudhry ◽  
Payal Sachdeva
Keyword(s):  
Drinking Water ◽  
Age Groups ◽  
Management Plan ◽  
Study Data ◽  
Sensitivity Analyses ◽  
North East ◽  
Sodium Magnesium ◽  
Primary Determinant ◽  
Semi Arid Region

Abstract Groundwater is the main source of water in the study area (Rupnagar District, Punjab), and its quality is essential since it is the primary determinant of the suitability of groundwater for drinking and irrigation purposes. In this study, data from 28 years have been used to evaluate the adequacy of groundwater for domestic and irrigation purposes and assess the potential human health impacts of nitrate contaminants. Results of sodium adsorption ratio, percentage sodium, magnesium hazard ratio, Kelley ratio, and residual sodium carbonate illustrate that most of the sampling locations were suitable for irrigational purposes and drinking water quality of the region mostly belonged to the ‘good’ class. The maximum nitrate concentration was observed in the northern and north-east parts of the area. Among the three age groups, children > female > male was found to be more prone to health risks with oral ingestion of nitrate. Uncertainties in the risk estimates were quantified using Monte Carlo simulation and sensitivity analyses. Thus, a proper management plan should be adopted by the decision-makers to improve the quality of drinking water in this area to avoid major health problems in the near future.

scholarly journals Discriminating raining from non-raining clouds at mid-latitudes using multispectral satellite data

2006 ◽  
Vol 6 (12) ◽  
pp. 5031-5036 ◽  
Author(s):  
T. Nauss ◽  
A. A. Kokhanovsky
Keyword(s):  
Satellite Data ◽  
Cloud Droplet ◽  
Threshold Value ◽  
Convective Precipitation ◽  
Droplet Radius ◽  
Concept Model ◽  
Cloud Properties ◽  
Frontal Systems ◽  
Precipitating Clouds ◽  
Cloud Top Temperature

Abstract. We propose a new method for the delineation of precipitation using cloud properties derived from optical satellite data. This approach is not only sufficient for the detection of mainly convective precipitation by means of the commonly used connection between infrared cloud top temperature and rainfall probability but enables the detection of stratiform precipitation (e.g., in connection with mid-latitude frontal systems). The scheme presented is based on the concept model, that precipitating clouds must have both a sufficient vertical extent and large enough droplets. Therefore, we have analysed MODIS scenes during the severe European summer floods in 2002 and retrieved functions for the computation of an auto-adaptive threshold value of the effective cloud droplet radius with respect to the corresponding optical thickness which links these cloud properties with rainfall areas on a pixel basis.

Adapting the COSP Radar Simulator to Compare GCM Output and GPM Precipitation Radar Observations

2021 ◽  
Author(s):  
Emily M. Riley Dellaripa ◽  
Aaron Funk ◽  
Courtney Schumacher ◽  
Hedanqiu Bai ◽  
Thomas Spangehl
Keyword(s):  
General Circulation ◽  
Cloud Cover ◽  
Convective Cloud ◽  
Convective Precipitation ◽  
Model Output ◽  
Precipitation Radar ◽  
Cloud Coverage ◽  
Convective Rain ◽  
Grid Algorithm ◽  
Radar Simulator

AbstractComparisons of precipitation between general circulation models (GCMs) and observations are often confounded by a mismatch between model output and instrument measurements, including variable type and temporal and spatial resolution. To mitigate these differences, the radar-simulator Quickbeam within the Cloud Feedback Model Intercomparison Project (CFMIP) Observation Simulator Package (COSP) simulates reflectivity from model variables at the sub-grid scale. This work adapts Quickbeam to the dual-frequency Precipitation Radar (DPR) onboard the Global Precipitation Measurement (GPM) satellite. The longer wavelength of the DPR is used to evaluate moderate-to-heavy precipitation in GCMs, which is missed when Quickbeam is used as a cloud radar simulator. Latitudinal and land/ocean comparisons are made between COSP output from the Community Atmospheric Model version 5 (CAM5) and DPR data. Additionally, this work improves the COSP sub-grid algorithm by applying a more realistic, non-deterministic approach to assigning GCM grid box convective cloud cover when convective cloud is not provided as a model output. Instead of assuming a static 5% convective cloud coverage, DPR convective precipitation coverage is used as a proxy for convective cloud coverage. For example, DPR observations show that convective rain typically only covers about 1% of a 2° grid box, but that the median convective rain area increases to over 10% in heavy rain cases. In our CAM5 tests, the updated sub-grid algorithm improved the comparison between reflectivity distributions when the convective cloud cover is provided versus the default 5% convective cloud cover assumption.

Sign in / Sign up

Export Citation Format

Share Document